Cataract surgery takes longer in functionally monocular patients.

BACKGROUND AND OBJECTIVES: To determine differences in the amount of work involved in caring for functionally monocular patients who undergo cataract surgery compared with binocularly sighted patients. PATIENTS AND METHODS: This was a retrospective study that included 100 consecutive functionally monocular patients and 100 binocularly sighted control patients matched by age (+/-5 years) and date of surgery ( +/-1 year). Office records were reviewed to determine several measures of office and operating room work effort. RESULTS: There was no difference between groups in preoperative telephone calls (P = .136), postoperative telephone calls (P = .580), preoperative office visits (P = .875), postoperative office visits (P = .601), or the number of times surgery was scheduled (P = 1.00). Monocular patients required more time for surgery (37.4 minutes) than binocular patients (32.4 minutes) (P= .010). CONCLUSIONS: It takes longer to perform cataract surgery on functionally monocular patients than on binocularly sighted patients.     

Evidence that peroxynitrite affects human osteoblast proliferation and differentiation.

Peroxynitrite (PN), a nitric oxide (NO*)-derived anion, has been associated with NO* damage in various cell types. We examined the effects of adding PN to cultured human osteoblast-like (hOB) cells obtained after hip arthroplasty. Exposure to PN (0.1-0.4 mM) decreased both hOB proliferation and differentiation, measured by [3H]thymidine uptake and alkaline phosphatase production, respectively. Incubation with 3-morpholinosydnonimine (SIN-1; 0.25-1 mM), an NO* and O2- donor that leads to PN release, also reduced both hOB proliferation and differentiation. Coincubation with both superoxide dismutase (SOD; 100 U/ml) and catalase (CAT; 50 U/ml), rendering SIN-1 a pure NO* donor, reversed its effects on hOB proliferation and differentiation. However, SIN-1-induced NO* production, measured by nitrite release to the hOB medium, was not altered by cotreatment with SOD and CAT. Expression of nitrotyrosine by hOB, a marker of PN action, was significantly increased after SIN-1 addition, as compared with untreated cells, as revealed by Western blot analysis. Interleukin-1alpha (IL-1alpha) and interferon gamma (IFN-gamma) but not tumor necrosis factor alpha (TNF-alpha) also significantly increased nitrotyrosine expression in these cells. These data show that PN is at least partially responsible for osteoblast derangement by NO* and that cytokines released during inflammatory arthropathies can induce PN production in hOB cells.     

Heparin effect on ionised calcium concentration

The effect of heparin on plasma ionised calcium was studied by adding it in increasing amounts to whole blood from 10 normal subjects. There was no significant change in ionised calcium from the addition of 1 U/ml but a significant fall of 0.02 mmol/1 when 2 U/ml were added and a progressive further fall with increasing concentrations. Heparin from three different manufacturers produced similar results. The effect of heparinisation in vivo was studied during regular haemodialysis on 10 patients with chronic renal failure. Following intravenous injection of 10000 U of heparin there was a consistent and significant fall averaging 0.03 mmol/l.     

Screening for coronary artery disease in assymptomatic adults is not recommended, so why is it still done?

The rationale behind screening for asymptomatic coronary artery disease is that it may diagnose advanced disease that, while frequently without symptoms, may present for the first time as sudden death. Identifying significant coronary artery disease would enable intervention against risk factors and, if necessary, preventive revascularization. The most recent evidence shows that screening for coronary artery disease with resting electrocardiogram, exercise tolerance testing or electron-beam computerized tomography in low-risk patients does more harm than good, and should not be performed. This negative recommendation is based on the fact that the use of the aforementioned tests has a negative benefit-harm ratio, because the false-positive rate cancels out any benefit from the occasional detection of real disease, inducing a cascade of further testing (sometimes with angiography) and overdiagnosis of a disease that is not in fact present, with negative psychological and financial consequences, such as increased insurance premiums. We feel that the Portuguese Society of Cardiology should intervene with the institutions performing screening of coronary heart disease in asymptomatic patients, and recommend abandoning a practice that is of little use and, overall, harmful.